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941.
Anal fistula surgery offers very little in the way of new developments. As early as the 14th century John of Arden defined the rules for surgical therapy. The numerous classifications adopted are often contradictory and unclear, and no clearly defined pathogenesis of the condition has been established. Complex anal fistula with a recess above the elevator ani muscles requires very careful and meticulous therapeutic treatment because of the risk of damaging the sphincter. In the case reported here the patient presented a very complex fistula which was followed by onset of severe haemorrhagic colitis without any clinical, endoscopic, radiological, or histological evidence of inflammatory bowel disease prior to surgical treatment.  相似文献   
942.
The risk of diabetic nephropathy is partially genetically determined. Diabetic nephropathy is linked to a gene locus on chromosome 18q22.3-q23. We aimed to identify the causative gene on chromosome 18 and to study the mechanism by which the product of this gene could be involved in the development of diabetic nephropathy. DNA polymorphisms were determined in 135 case (diabetic nephropathy) and 107 control (diabetes without nephropathy) subjects. The effect of carnosine on the production of extracellular matrix components and transforming growth factor-beta (TGF-beta) after exposure to 5 and 25 mmol/l d-glucose was studied in cultured human podocytes and mesangial cells, respectively. A trinucleotide repeat in exon 2 of the CNDP1 gene, coding for a leucine repeat in the leader peptide of the carnosinase-1 precursor, was associated with nephropathy. The shortest allelic form (CNDP1 Mannheim) was more common in the absence of nephropathy (P = 0.0028, odds ratio 2.56 [95% CI 1.36-4.84]) and was associated with lower serum carnosinase levels. Carnosine inhibited the increased production of fibronectin and collagen type VI in podocytes and the increased production of TGF-beta in mesangial cells induced by 25 mmol/l glucose. Diabetic patients with the CNDP1 Mannheim variant are less susceptible for nephropathy. Carnosine protects against the adverse effects of high glucose levels on renal cells.  相似文献   
943.
BACKGROUND: Vascular access thrombosis is an important cause of morbidity in patients with end-stage renal failure on maintenance hemodialysis (MHD). However, little is known about its risk factors. The present study was undertaken to evaluate the role of coagulation factors, fibrinolytic factors, and anti-phospholipid antibodies (aPL). In particular, we have evaluated the role of anti-protein C and anti-protein S antibodies in patients on MHD with and without thrombosis because no data are available in the literature. METHODS: The study group comprised 30 patients with thrombotic complications (TC), 40 patients matched for age, sex, and dialytic age with no thrombotic complications (NTC) and 400 controls. We have measured: anti-protein C antibodies, anti-protein S antibodies, anticardiolipin antibodies (ACA), anti-beta2-glycoprotein antibodies (beta2-GPI), and anti-prothrombin antibodies (aPT), along with prothrombin time, fibrinogen, plasminogen, protein C, protein S, anti-thrombin III, APC-resistance test, D-dimer, tissue-type plasminogen's activator, plasminogen activator inhibitor-1 (PAI-1), prothrombin fragment 1+2, factors of the intrinsic and extrinsic pathway, C-reactive protein, and homocysteine. RESULTS: There were no significant differences between groups for prothrombin time, fibrinogen, plasminogen, protein C, protein S, anti-thrombin III, activated protein C (APC) resistance, D-dimer, tPA, C-reactive protein, Factors II, X, and VII. The anti-beta2-GP1 and aPT were elevated in both TC and NTC patients, compared to the control group. Significant differences between TC and NTC groups were found for anti-protein C and anti-protein S antibodies, ACA-IgM, PAI-1, Factor VIII, prothrombin fragments 1+2, and homocysteine. CONCLUSION: The most novel finding was a significant elevation of anti-protein C antibodies and anti-protein S antibodies in the TC group (i.e., in patients on MHD with thrombosis of vascular access). It indicates that other pathogenetic mechanisms in addition to endothelial damage may cause hypercoagulability in uremia.  相似文献   
944.
Angiogenesis in the human heart: Gene and cell therapy   总被引:3,自引:0,他引:3  
Tirziu D  Simons M 《Angiogenesis》2005,8(3):241-251
The concept of therapeutic angiogenesis – stimulation of new vessels growth to restore blood supply to ischemic tissue has been studied in a number of clinical trials in patients with advanced coronary and peripheral arterial disease. This review discusses the main biological processes underlying new vessel growth and addresses applications of growth factor and cell therapy based on the stimulation of angiogenesis. While still very young and controversial, cell therapy has an enormous potential that is yet to be explored. Multiple questions remain unanswered including the choice of the best cell type, patient selection and the mechanism of action. Nevertheless, much should be expected in this area in the next decade with the likely emergence of new therapies for treatment of ischemic diseases.  相似文献   
945.
946.
The aim of this study was to evaluate the performance of two different glass-ionomer cements: a high-density (Ketac Molar - ESPE) and a resin-modified cement (Fuji VIII - GC) using the Atraumatic Restorative Treatment technique to restore multisurface cavities in permanent teeth. A total of 60 ART restorations (30 with each material) were placed in schoolchildren (9-16 years of age) by two operators. After a period of 6 months, two independent examiners evaluated 59 restorations according to the criteria used in previous ART studies. Data were submitted to McNemar and Fischer tests. The success rate of the treatment was 98.3%. One restoration (Ketac Molar) was replaced by another material and was recorded as failure. The success rates of the restorations were 100% and 96.6% for Fuji VIII and Ketac Molar, respectively. There was no statistically significant difference in the restorations success between baseline and 6 months (p>0.05). In the same way, no significant differences were found between materials, cavity types or operators (p>0.05). The ART approach was highly appropriate and effective in restorations involving two or more tooth surfaces, after 6 months. The results showed a promising performance of the ART technique with both materials.  相似文献   
947.
948.
The principles of positron emission tomography (PET), recently introduced as a diagnostic procedure into the health sciences, are described. The principle clinical applications apply to a particular group of specialties: cardiology, neurology, psychiatry, and above all oncology. Positron emission tomography is a non-invasive diagnostic imaging technique with clinical applications. It is an excellent tool for the study of the stage and possible malignancy of tumors of head and neck, the detection of otherwise clinically indeterminate metastases and lymphadenopathies, and likewise for the diagnosis of relapses. The only tracer with any practical clinical application is fluor-desoxyglucosa-F18 (FDG). PET detects the intense accumulation of FDG produced in malignant tumors due to the increased glycolytic rate of the neoplastic cells. With the introduction of hybrid systems that combine computerized tomography or magnetic resonance with positron emission tomography, important advances are being made in the diagnosis and follow-up of oncologic pathology of head and neck.  相似文献   
949.
The chromosomal polymorphism of Anopheles funestus sensu stricto from Angola was analyzed from indoor-resting samples collected in 11 peri-urban and rural sites of the Luanda and Huambo Provinces, which are > 450 km apart and have distinct eco-climatic conditions. Five polymorphic paracentric inversions were observed (scored chromatids range = 202 to 248): 2Ra, 2Rh, 3Ra, 3Rb, and 3La. Inversions 3Rb and 3La were highly polymorphic; the 2Ra and 3Ra arrangements were absent in Luanda. No significant departures from Hardy-Weinberg and linkage equilibria were found at the locality, commune, or province level (sites 相似文献   
950.
Relative antiinflammatory and immunosuppressive potencies of glucocorticoids (GC) were previously well defined. Nonetheless, GC also regulate cell proliferation and programmed death (apoptosis). The aim of this study was to determine the relative potency of different GC on the modulation of cell survival. The GC-sensitive lymphoblast cell line CEM-c7/14 was submitted to 48 h-exposure to GC (dose-response curve from 10(-8) to 10(-5) M). Cell survival was analyzed employing the DimethylTiazol-Tetrazolium (MTT) test. For each GC at least 4 experiments were performed in quadruplicate. Responses to different GC at the same molarity were analyzed by ANOVA on Ranks. Cell responses to the same GC in different concentrations were tested by repeated measures ANOVA. The EC50 for each GC was calculated with the GraphPad Prism 3.0 software. The use of low concentrations (10(-8) and 10(-7) M) of hydrocortisone and methylprednisolone determined a similar effects on cell survival, which was less prominent than that observed with betamethasone, budesonide or momethasone. Momethasone was the most potent GC, inducing the most intense dexamethasone reduction on cell survival at the lowest concentration (10(-8) M). Momethasone and methylprednisolone were the two GC with the strongest impact on cell survival. Our findings suggest that antiproliferative and apoptotic potencies of GC are different from those previously reported antiinflammatory and immunosuppressive actions.  相似文献   
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